BACKGROUND/OBJECTIVE Weight loss is a predictor of shorter survival in amyotrophic lateral sclerosis (ALS). We performed serial measures of body composition using Dual-energy X-ray Absorptiometry (DEXA) in ALS patients to explore its utility as a biomarker of disease progression. METHODS DEXA data were obtained from participants with ALS (enrollment, at 6- and 12- months follow ups) and Parkinson's disease (enrollment and at 4-month follow up) as a comparator group. Body mass index, total lean mass index, appendicular lean mass index, total fat mass index, and percentage body fat at enrollment were compared between the ALS and PD cohorts and age-matched normative data obtained from the National Health and Nutrition Examination Survey database. Estimated monthly changes of body composition measures in the ALS cohort were compared to those of the PD cohort and were correlated with disease progression measured by the Revised Amyotrophic Lateral Sclerosis Functional Rating Scale (ALSFRS-R). RESULTS The ALS cohort (N = 20) had lower baseline total and appendicular lean mass indices compared to the PD cohort (N = 20) and general population. Loss in total and appendicular lean masses were found to be significantly associated with follow-up time. Low baseline percentage body fat (r = 0.72, p = 0.04), loss of percentage body fat (r = 0.81, p = 0.01), and total fat mass index (r = 0.73, p = 0.04) during follow up correlated significantly with monthly decline of ALSFRS-R scores in ALS cohort who had 2 or more follow-ups (N = 8). CONCLUSION Measurement of body composition with DEXA might serve as a biomarker for rapid disease progression in ALS.

中文翻译：

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脂肪质量减少与肌萎缩性侧索硬化症患者疾病进展更快相关：在一项前瞻性研究中探索双能X线吸收法的实用性。

背景/目的体重减轻是肌萎缩性侧索硬化症（ALS）生存期缩短的预测指标。我们使用双能X线骨密度仪（DEXA）对ALS患者进行了一系列身体成分测量，以探索其作为疾病进展的生物标志物的作用。方法DEXA数据来自作为对照组的ALS（入组，随访6个月和12个月）和帕金森氏病（入组并随访4个月）。比较了ALS和PD队列中的体重指数，总瘦体重指数，阑尾瘦体重指数，总脂肪质量指数和入院时的体脂百分比，并从国家健康和营养检查调查数据库中获得了年龄匹配的规范数据。将ALS人群与PD人群的估计每月身体成分变化进行比较，并将其与通过修订的肌萎缩性侧索硬化症功能评定量表（ALSFRS-R）测得的疾病进展相关。结果与PD队列（N = 20）和一般人群相比，ALS队列（N = 20）的基线总和阑尾瘦体重指数较低。发现总的和阑尾瘦质量的损失与随访时间显着相关。随访期间低基线体脂百分比（r = 0.72，p = 0.04），体脂百分比减少（r = 0.81，p = 0.01）和总脂肪质量指数（r = 0.73，p = 0.04）与以下因素显着相关：随访2个或更多（N = 8）的ALS队列中ALSFRS-R得分的月度下降。